adv7152 Analog Devices, Inc., adv7152 Datasheet - Page 21

• Manufacturer Part Number: adv7152
• Description: Cmos 220 Mhz True-color Graphics Triple 10-bit Video Ram-dac
• Manufacturer: Analog Devices, Inc.

COMMAND REGISTER 3 (CR3)
(Address Reg (A7–A0) = 07H)
This register contains a number of control bits as shown in the
diagram. CR3 is a 10-bit wide register. However for program-
ming purposes, it may be considered as an 8-bit wide register
(CR38 and CR39 are both reserved).
The diagram shows the various operations under the control of
CR3. This register can be read from as well written to. In read
mode, CR38 and CR39 are both returned as zeros.
COMMAND REGISTER 3-BIT DESCRIPTION
PRGCKOUT Frequency Control (CR31–CR30)
These bits specify the output frequency of the PRGCKOUT
output. PRGCKOUT is a divided down version of the pixel
CLOCK.
REV. B
*
THESE BITS ARE READ-ONLY
RESERVED BITS.
A READ CYCLE WILL RETURN
ZEROS "00".
CR37 CR36
0
0
1
1
RESERVED*
CR39 CR38
0
1
0
1
PIXEL MULTIPLEX CONTROL
1:1 MUXING: LOADOUT = CLOCK 1
2:1 MUXING: LOADOUT = CLOCK 2
RESERVED
RESERVED
CR37
Command Register 3 (CR3) (CR39–CR30)
CR36
CR35 CR34 CR33 CR32
EXTRA BLANK PIPELINE DELAY CONTROL
0
0
0
–
–
1
(ADDS TO PIXEL PIPELINE DELAY;
CR35
0
0
0
–
–
1
–21–
CR34
0
0
1
–
–
1
BLANK Pipeline Delay Control (CR35–CR32)
These bits specify the additional pipeline delay that can be
added to the BLANK function, relative to the overall device
pipeline delay (t
video DAC from a shorter pipeline than the video pixel data,
this control is useful in deskewing the pipeline differential.
Pixel Multiplex Control (CR36)
These bits specify the device’s multiplex mode. It, therefore,
also determines the frequency of the LOADOUT signal.
LOADOUT is a divided down version of the pixel CLOCK.
Revision Register
(Address Reg (A7–A0) = 0BH)
This register is a read only register containing the revision of
silicon.
0
1
0
–
–
1
CR33
BLANK PIPELINE DELAY
t
t
t
t
PD
PD
PD
PD
–
–
CR32
+ 1 x LOADOUT
+ 2 x LOADOUT
+ 15 x LOADOUT
–
–
PD
). As the BLANK control normally enters the
–
–
CR31 CR30
t
FREQUENCY CONTROL
PD
0
0
1
1
CR31
)
PRGCKOUT
0
1
0
1
CR30
CLOCK 4
CLOCK 8
CLOCK 16
CLOCK 32
ADV7152